Such a chair assembly is known from U.S. Pat. No. 3,628,829. In the case of this chair assembly the two hinge axes are placed perpendicular to each other, so that only tilting movements of the chair are possible. Moreover, these tilting movements are always jolting movements, since the tilting movements occur about a fixed tilting point situated in the centre underneath the chair. A chair placed on the assembly is therefore also provided with spring elements in the top frame, in order to be able to absorb these jolts.